Almost every society on the Earth views the protection of natural landscapes as an important charge for all people on the planet.

The fervor to conserve the land and its biological diversity for future inhabitants of the earth is seen as a mission which must be accomplished by many individuals.

But at what point does the fervor start to restrict the possible rights of future generations?

When do actions people take now violate the options of people who will live 50, 100 or 200 years in the future?

Citizens of the United States have benefited from decisions made before the turn of the last century concerning national parks, forests and various land and wildlife preserves. People flock to see the natural wonders at Yellowstone and the Grand Canyon.

Without protection, many of the places would be different or would be in private hands.

But the days of creating new realms out of government land is almost over, primarily because much of the property is gone or has been developed.

However, some government agencies as well as private land trusts are finding a new way to restrict land without transferring ownership.

A conservation easement is placed on a property by the owner. Depending on how it is created and worded, the easement restricts certain activities on the land in question, literally forever or as long as the law supports the restraint.

"If you want a picture of the future, imagine a boot stamping on a human face - forever," stated George Orwell in 1984, a book telling the story of a totally controlled society.

Julia D. Mahoney is a professor of law at the University of Virginia and a land law expert, particularly in conservation servitude.

In a paper she wrote in December 2001 titled "Perpetual Restrictions on Land and the Problem of the Future," Mahoney cites many reasons the restriction of future property owners rights could be a problem and a burden.

The law professor bases her paper on what she calls two erroneous assumptions that conservationists who wish to place easements make.

First, Mahoney indicates that the idea for the easements is based on the assumption that land owners are capable of making long-term preservation decisions and can pick out the types of properties that should be protected. The second assumption in error is that the present generation represents nature's last or nearly last chance, because it is felt once land is developed it will never go back to being undeveloped.

While conservation easements are put on the land by present owners, often for tax breaks or because of money support from private entities, one has to ask what benefit the easements will be to people who live in the future.

The land owners tend to assume that what the future generations will see as worth saving will be the same as what people feel is important today.

However, times change and priorities differ, not only from generation to generation, but also from multigeneration to multigeneration.

"The fact that conservation servitudes offer flexibility to the parties who are initially involved in their negotiation does not mean their flexibility is infinite," Mahoney writes in her paper.

The problem is that the only real constant in the world is change.

For instance when the San Rafael Swell was first discovered by Spanish explorers, the parties often described it as an inhospitable land, one where none of them would want to live or try to survive.

Some people called lands like the Swell worthless.

Yet today, that land is valued by so many groups that a fight about a referendum as to what to do with the San Rafael drew national attention two years ago.

The value of the San Rafael Swell has changed, from primarily a ranching based piece of property only 60 years ago to what is currently considered as one of the most beautiful outback tourist places in the nation. The land on the desert means money to people who live around it because of recreation and mineral extraction.

The so-called "worthless" land of yesteryear brings cries of emotion out of people when the uses that it accommodates today are challenged.

Conservation easements assume that all lands under their power will be never changing or always worth what they are being protected for. So the biggest problem with these instruments of protection, in the eyes of opponents, is that the law, when it comes to them, will remain in place regardless of the circumstances.

Last August, the South Dakota Farm Bureau began a petition drive to eliminate the perpetuity of conservation easements by either setting a sunset clause of 50 years on the legal restrictions or by giving any new owner the chance to buy out the easement when the property is purchased. Of course, most conservation groups are opposed to this idea. They believe the basis for the conservation easement that people put on their land is often largely not for personal gain, but because they want to see the land they have owned stay the same as it is today, forever.

But will that emotional attachment to the "land as it is today" have the same connection with a future generation.

The argument concerns the rights of a future owners having a full estate with which they can work or a split estate with which they may not be able to deal effectively.

What people socially want or think is good today may not be the same in the world of tomorrow.

"The stark, albeit to some unpalatable, reality is that ways of life have changed throughout human history, with succeeding generations choosing to live differently from their parents and ancestors," noted Mahoney in her paper. "Preservationists should question whether striving to prolong forms of social organization is a sensible goal."

The law professor also points out that "development and preservation are fluid categories, not fixed ones."

How society views preservation and how the cultural norms may change could encounter a roadblock with perpetual conservation easements. A perpetual easement is created to make undoing the restrictions almost impossible.

People tend to think that their generation is the smartest and best that has ever lived.

If that were true and human kind is in an upward spiral toward knowing what is best with each succeeding generation, does that mean people today should make choices when it comes to private lands for the individuals who will believe they are from the best generation 200 years in the future?

Or will future generations have to live with a boot, as Orwell put it, that was applied by people from the past?

"The present generation should recognize that our definition of development is unlikely to be their definition of development, just as our conclusions about which land uses pose the greatest threats of environmental harm will not be theirs," notes Mahoney.